Question

D-glucose and L-glucose are examples of:
A. diastereomers
B. enantiomers
C. anomers
D. epimers

Answer 1

Hint:D-glucose is formed when glucose rotates the plane polarized light in the right direction (dextrorotation) and L-glucose is formed when glucose rotates the plane polarized light in the left direction (levorotation). The D-glucose and L-glucose is non-superimposable mirror image of each other.

Complete step by step answer:

When the hydroxyl group present on the carbon atom of forth position and fifth position is localized at the right side of the fischer projection. Then the glucose shows D-configuration.
When the hydroxyl group present on the carbon atom of forth position and fifth position is localized at the left side of the fischer projection. Then the glucose shows L-configuration.
Enantiomers are classified as chiral molecules which are mirror images of each other. The molecules cannot overlap each other to form a single molecule, this means that enantiomers are non-superimposable on each other. The chiral molecules which contain one or more than one stereocenters can form enantiomers.
As can be seen that the D-form of glucose differs from the L-form on the basis of the hydroxyl group attached to the fourth position of carbon and fifth position of carbon. When they are placed upside down, they do not form the single molecule.
D-glucose and L-glucose are examples of enantiomers
Therefore, the correct option is B.

Note:
When the enantiomers are flipped to 180 degree using the Wedge-Dash notation, the group or atom which are attached to the wedged bond become dashed and the group or atom attached to the dashed bond become wedged.